Fix error message for deleteRule()

Previous to this CL, deleteRule on an empty style sheet would throw a
confusingly-worded IndexSizeError. Now, it properly throws a RangeError.

For example:

const styleEl = document.createElement('style');
--> Uncaught RangeError: Failed to execute 'deleteRule' on 'CSSStyleSheet': The index provided (0) is outside the range [0, 0).

Bug: 949523
Change-Id: I306409f53be88f4bead261dd171466fd3aad5565
Auto-Submit: Mason Freed <>
Commit-Queue: Chris Harrelson <>
Reviewed-by: Chris Harrelson <>
Cr-Commit-Position: refs/heads/master@{#650697}
2 files changed